I was an only child, so I never had the pleasure of being compared to my sibling. This didn't stop my parents from comparing me to their friend's kids, so I know how real the pang of comparison is. Everyone has their own talents, and some of them are more easily discovered earlier in life. If you're good at school, excel in a certain extracurricular, or manage to make a lot of friends in your early life, then those things are easily celebrated. Some of us are late bloomers, but that doesn't mean we don't bloom anyway.
But it's hard not to measure yourself against your peer group, especially if someone close to you seems to be winning the game. So that said, I sympathize with the subject of this Reddit thread, but there is a proper way to deal with those feelings, and this definitely wasn't it. Read on for the details.